Abstract
Background
Respiratory syncytial virus (RSV) is one of the important pathogens found in patients with acute respiratory infection (ARI), but there are few studies on RSV infection among elderly people in China.
Methods
This study collected data on the RSV‐infected population among the hospitalized patients with ARI admitted to the Department of Respiratory Medicine of our hospital from November 2023 to February 2024 and analyzed the clinical data of the elderly (≥ 60 years old) grouped by age. Patients admitted to other departments (e.g., general internal medicine, geriatrics) were not included, potentially introducing selection bias toward more severe respiratory presentations.
Results
The total infection rate was 12.16%, and the main symptoms were cough (97.78%), sputum (95.56%), and dyspnea (68.89%); 100% of the patients had comorbidity, and 97.78% of the patients had two or more comorbidities. Laboratory findings were mainly elevated CRP (84.4%), lymphopenia (64.44%), elevated hs‐cTni (51.11%), elevated N‐terminal pro‐B‐type natriuretic peptide (NT‐proBNP) (37.78%), decreased PaO2 (88.89%), and elevated PaCO2 (44.44%). The rate of mixed bacterial and viral infection was 37.78%; 95.56% of the patients had lung imaging changes; 100% of the patients received respiratory therapy support, and 91.11% of the patients used antibiotics. The discharge rate was 93.33%, and the mortality rate was 6.67%.
Conclusion
There was no obvious abnormal seasonality in the infection rate; the infection rate, the proportion of lymphopenia, and the proportion of respiratory failure were higher than in most other studies. The statistical data are only statistically significant in terms of the decrease in PaO2/FiO2 (P/F ratio), the elevation in the NT‐proBNP, and some imaging performances. It may be that the number of samples is not large enough to cause the difference to be insignificant. Furthermore, this study exclusively included patients admitted to the Respiratory Medicine Department, which may reflect department‐specific referral bias and potentially underestimate the true burden of RSV in the broader elderly population. Patients admitted to other departments (e.g., general internal medicine, geriatrics) were not included, potentially introducing selection bias toward more severe respiratory presentations.
Keywords: acute respiratory infection, elderly patients, pneumonia, respiratory failure, respiratory syncytial virus
1. Introduction
Respiratory syncytial virus (RSV) is one of the important pathogens identified in patients with acute respiratory infection (ARI) and is increasingly recognized as the cause of infection in high‐risk adults, including those with chronic lung disease and heart disease. Studies on RSV infection have mainly focused on children, and there are few studies on the elderly, especially in China. After the COVID‐19 epidemic, there have been abnormal outbreaks of RSV, such as high morbidity, off‐season outbreaks, multivirus compound infections, and others [1, 2].
This article reviews the data of RSV infection among ARI patients admitted to the Department of Respiratory Medicine of Beijing Fengtai You’anmen Hospital from November 2023 to February 2024 and grouped the elderly (≥ 60 years old) to statistically analyze the infection rate, seasonality, comorbidity, clinical manifestations, laboratory examinations, treatment, and outcome.
2. Materials and Methods
2.1. Study Population
From November 1, 2023, to February 29, 2024, all patients who were hospitalized in the hospital due to ARI were collected by nasopharyngeal swabs within 24 h of admission and sent for nucleic acid testing of chlamydia, mycoplasma, and respiratory viruses. Patients admitted to other departments (e.g., general internal medicine, geriatrics) were not included, potentially introducing selection bias toward more severe respiratory presentations. RSV patients were screened according to the Diagnosis of Human Respiratory Syncytial Virus Infection (CT/CPMA 028‐2023) [3], and the old patients (≥ 60 years old) were divided into two groups according to age for comparison: the younger‐old group (60–79 years old) and the oldest‐old group (≥ 80 years old). This study was conducted in accordance with the Declaration of Helsinki and was approved by the Medical Ethics Committee of Beijing Fengtai YouAnMen Hospital (20240506), and patient consent statements have been granted an exemption. Written informed consent was obtained from all participants prior to their inclusion in the study. All procedures involving human subjects were performed in compliance with institutional and national ethical standards. No animal experiments were conducted in this study.
2.2. Pathogenic Detection
Six types of respiratory virus (RSV, influenza A virus, influenza B virus, adenovirus, parainfluenza virus Type 1, and parainfluenza virus Type 3), were detected by the commercial real‐time fluorescence PCR technology test kit (Respiratory Virus Six‐Fold Test Kit, Beijing Zhuocheng Wison Biological Technology Co., Ltd.). The nucleic acid extraction and detection steps were carried out in strict accordance with the instructions of the kit. The judgment criteria for positive specimens are shown in Table 1.
TABLE 1.
The judgment criteria for positive specimens.
| Specimen | Value |
|---|---|
| Leukocytopenia | < 3.5 ∗ 109/L |
| Leukocytosis | > 9.5 ∗ 109/L |
| Elevated absolute neutrophil count | > 6.3 ∗ 109/L |
| Elevated absolute neutrophil % | > 75% |
| Lymphopenia | < 1.1 ∗ 109/L |
| Decreased lymphocyte % | < 20% |
| Elevated CRP | > 6 mg/L |
| Elevated PCT | > 0.5 ng/mL |
| Elevated ALT | > 50 U/L (male) |
| > 40 U/L (female) | |
| Elevated AST | > 40 U/L (male) |
| > 35 U/L (female) | |
| Elevated NT‐proBNP | > 900 pg/mL (50–75 years) |
| > 1800 pg/mL (> 75 years) | |
| Elevated hs‐cTni | > 0.036 ng/mL (male) |
| > 0.02 ng/mL (female) | |
| Abnormal blood gas pH | > 7.45 or < 7.35 |
| Decreased PaO2 | < 100 − (age ∗ 0.33) ± 5 mmHg |
| Elevated PaCO2 | > 45 mmHg |
| Respiratory failure | PaO2/FiO2 < 300 mmHg |
| Mild respiratory failure | 200 mmHg < PaO2/FiO2 < 300 mmHg |
| Moderate respiratory failure | < 100 mmHg PaO2/FiO2 < 200 mmHg |
| Severe respiratory failure | PaO2/FiO2 < 100 mmHg |
2.3. Specimen and Data Collection
The following data were collected from the enrolled population: demographic data; comorbidity, including hypertension, stroke, coronary heart disease, heart failure, myocardial infarction, atrial fibrillation, chronic obstructive pulmonary disease (COPD), bronchiectasis, asthma, tumor, renal insufficiency; clinical manifestations, including cough, sputum production, dyspnea, fever, sore throat, fatigue, rhinorrhea, nasal congestion; laboratory examinations on admission, including blood routine, inflammatory markers, liver function, N‐terminal pro‐B‐type natriuretic peptide (NT‐proBNP), hs‐cTni, blood gas analysis; etiological examination; chest CT images before or within 24 h of admission; treatment and outcome.
2.4. Statistical Analysis
A continuous variable is expressed as mean ± standard deviation (, categorical variable is expressed as number and percentage, and inter‐group comparison is carried out by the χ 2 test, Fisher’s exact test, or Mann–Whitney test. A two‐sided α of less than 0.05 was considered statistically significant. Cases with missing data of a variable were excluded from the statistical analyses on this variable. All statistical analyses were done using SPSS statistical software Version 26.0 (SPSS Inc., Chicago, IL, USA).
3. Results
3.1. Demographic Characteristics
Between November 1, 2023, and February 29, 2024, a total of 443 patients with ARI (aged 73 ± 16.1 years, 227 males and 217 females) were hospitalized, including 370 patients aged ≥ 60 years (aged 79 ± 10.0 years, 187 males and 183 females), among whom 45 patients (aged 82 ± 10.8 years, 21 males and 24 females) met the diagnostic criteria for RSV infection and were finally included in this study. The 45 patients were divided into two groups by age: the younger‐old group (60–79 years old, aged 70.2 ± 6.23 years, 9 males, 8 females) and the oldest‐old group (≥ 80 years old, aged 88.7 ± 5.66 years, 12 males, 16 females).
3.2. RSV Infection Rate of ARI Hospitalized Patients
The RSV infection rate is calculated on a monthly basis, as shown in Table 2. Specifically, RSV activity began at a low level in November (1.47%), increased in December (7.00%), peaked in January (24.11%), and then declined in February (11.11%), demonstrating a clear winter seasonal pattern in this elderly hospitalized population. The differences in the two groups of people in different months and the total RSV examination rate were not statistically significant.
TABLE 2.
RSV infection rate n/total (%).
| 60–79 years. | ≥ 80 years. | Total | p value | |
|---|---|---|---|---|
| 2023.11 | 0/36 (0.00) | 1/32 (3.13) | 1/68 (1.47) | 0.471 |
| 2023.12 | 5/55 (9.09) | 2/45 (4.44) | 7/100 (7.00) | 0.609 |
| 2024.1 | 7/46 (15.22) | 20/66 (30.3) | 27/112 (24.11) | 0.066 |
| 2024.2 | 5/48 (10.42) | 5/42 (11.90) | 10/90 (11.11) | 1.000 |
| Total | 17/185 (9.19) | 28/185 (15.14) | 45/370 (12.16) | 0.080 |
Note: Data are or n (%). p values were calculated by the Mann–Whitney test, χ 2 test, or Fisher’s exact test, as appropriate.
3.3. Comorbidity and Clinical Manifestation
All cases had comorbidity, and all of them were at high risk of RSV infection. Among them, hypertension (66.67%), stroke (57.78%), diabetes (40.00%), coronary heart disease (37.78%), and heart failure (35.56%) accounted for the top five. 44 patients (97.78%) had two or more comorbidities. The main clinical manifestations were cough (97.78%), sputum production (95.56%), dyspnea (68.89%), and fever (57.78%); the difference in clinical manifestations between the two groups was not statistically significant, as shown in Table 3.
TABLE 3.
Comorbidity and clinical manifestation n (%).
| 60–79 years (n = 17) | ≥ 80 years (n = 28) | Total (n = 45) | p value | |
|---|---|---|---|---|
| Comorbidity | ||||
| Hypertension | 12 (70.59) | 18 (64.29) | 30 (66.67) | 0.664 |
| Stroke | 6 (35.29) | 20 (71.43) | 26 (57.78) | 0.017 |
| Diabetes | 8 (47.06) | 10 (35.71) | 18 (40.00) | 0.451 |
| Coronary heart disease | 3 (17.65) | 14 (50.00) | 17 (37.78) | 0.030 |
| Heart failure | 5 (29.41) | 11 (39.29) | 16 (35.56) | 0.502 |
| COPD | 6 (35.29) | 5 (17.86) | 11 (24.44) | 0.336 |
| Tumor | 6 (35.29) | 5 (17.86) | 11 (24.44) | 0.336 |
| Renal insufficiency | 2 (11.76) | 4 (14.29) | 6 (13.33) | 1.000 |
| Atrial fibrillation | 1 (5.88) | 3 (10.71) | 4 (8.89) | 0.990 |
| Bronchiectasis | 1 (5.88) | 2 (7.14) | 3 (6.67) | 1.000 |
| Myocardial infarction | 0 (0.00) | 0 (0.00) | 0 (0.00) | 0.001 |
| Asthma | 2 (11.8) | 3 (10.7) | 5 (11.1) | 1.000 |
| Clinical manifestation | ||||
| Cough | 16 (94.12) | 28 (100.00) | 44 (97.78) | 0.378 |
| Sputum production | 15 (88.24) | 28 (100.00) | 43 (95.56) | 0.137 |
| Dyspnea | 12 (70.59) | 19 (67.86) | 31 (68.89) | 0.848 |
| Fever | 8 (47.06) | 18 (64.29) | 26 (57.78) | 0.257 |
| Sore throat | 4 (23.53) | 4 (14.29) | 8 (17.78) | 0.701 |
| Fatigue | 0 (0.00) | 4 (14.29) | 4 (8.89) | 0.275 |
| Rhinorrhea | 0 (0.00) | 1 (3.57) | 1 (2.22) | 1.000 |
| Nasal congestion | 1 (5.88) | 0 (0.00) | 1 (2.22) | 0.378 |
Note: Data are or n (%). p values were calculated by the Mann–Whitney test, χ 2 test, or Fisher’s exact test, as appropriate.
3.4. Laboratory Examination
There were 38 cases of an increase in CRP (84.4%), 32 cases of a decrease in the lymphocyte percentage (71.11), and 29 cases of a decrease in the absolute value of lymphocytes (64.44%); ALT increased in 3 cases (6.67%), AST increased in 10 cases (22.22%), NT‐proBNP increased in 17 cases (37.78%), and hs‐cTni increased in 23 cases (51.11%); there were 40 cases of a decrease in PaO2 (88.89%) and 20 cases of an increase in PaCO2 (44.44%). 27 cases had respiratory failure (60.00%). The data of two groups were statistically significant in respiratory failure count, moderate respiratory failure count, NT‐proBNP value, and AST value.
There were 12 cases of mixed infections with 2 pathogens (26.67%) and 5 cases of mixed infections with 3 pathogens (11.11%). The main pathogens were Klebsiella pneumoniae (5 cases, 11.1%), influenza A virus (4 cases, 8.89%), and Haemophilus influenzae (4 cases, 8.89%).
Forty three cases (95.56%) had lung imaging changes, mainly bronchial wall thickening, ground‐glass opacity and patchy exudate. Among them, 36 cases (80.00%) had bilateral changes and 7 cases (15.56%) had unilateral changes. The unilateral infiltration data of two groups was statistically significant, as shown in Table 4.
TABLE 4.
Laboratory examination n (%).
| 60–79 years (n = 17) | ≥ 80 years (n = 28) | Total (n = 45) | p value | |
|---|---|---|---|---|
| Blood routine | ||||
| Leukocytosis | 2 (11.76) | 3 (10.71) | 5 (11.11) | 0.248 |
| Leukocytopenia | 7 (41.18) | 6 (21.43) | 13 (28.89) | 1.000 |
| Abnormal leukocyte | 9 (52.94) | 9 (32.14) | 18 (40.00) | 0.566 |
| Elevated absolute neutrophil count | 8 (47.06) | 11 (39.29) | 19 (42.22) | 0.594 |
| Elevated absolute neutrophil % | 9 (52.94) | 17 (60.71) | 26 (57.78) | 0.553 |
| Lymphopenia | 11 (64.71) | 18 (64.29) | 29 (64.44) | 0.452 |
| Decreased lymphocyte % | 12 (70.59) | 20 (71.43) | 32 (71.11) | 0.516 |
| Elevated CRP | 15 (88.24) | 23 (82.14) | 38 (84.44) | 0.250 |
| Elevated PCT | 3 (17.65) | 6 (21.43) | 9 (20.00) | 0.101 |
| Abnormal blood gas pH | 7 (41.18) | 11 (39.29) | 18 (40.00) | 0.922 |
| Decreased PaO2 | 14 (82.35) | 26 (92.86) | 40 (88.89) | 0.364 |
| Elevated PaCO2 | 8 (47.06) | 12 (42.86) | 20 (44.44) | 0.200 |
| Severe respiratory failure | 1 (5.88) | 0 (0.00) | 1 (2.22) | 0.001 |
| Moderate respiratory failure | 3 (17.65) | 3 (10.71) | 6 (13.33) | 0.046 |
| Mild respiratory failure | 6 (35.29) | 14 (50.00) | 20 (44.44) | 0.137 |
| Respiratory failure | 10 (58.82) | 17 (60.71) | 27 (60.00) | 0.031 |
| NT‐proBNP | 4080.3 ± 9756.58 | 3966.0 ± 7023.8 | 4011.2 ± 8101.32 | 0.019 |
| ALT | 17.6 ± 9.19 | 30.0 ± 54.21 | 25.3 ± 43.26 | 0.972 |
| AST | 20.5 ± 14.66 | 34.3 ± 37.04 | 29.1 ± 31.08 | 0.017 |
| hs‐cTni | 0.06 ± 0.105 | 0.04 ± 0.034 | 0.05 ± 0.069 | 0.355 |
| Mixed bacterial and viral infection (other than RSV) | ||||
| None | 12 (70.59) | 16 (57.14) | 28 (62.22) | 0.367 |
| Mixed 1 | 4 (23.53) | 8 (28.57) | 12 (26.67) | 0.982 |
| Mixed 2 | 1 (5.88) | 4 (14.29) | 5 (11.11) | 0.704 |
| Type of mixed infection | ||||
| Bacteria | 2 (11.76) | 10 (35.71) | 12 (26.67) | 0.157 |
| Viruses | 2 (11.76) | 1 (3.57) | 3 (6.67) | 0.651 |
| Bacteria and viruses | 1 (5.88) | 1 (3.57) | 2 (4.44) | 1.000 |
| Infection pathogens | ||||
| Klebsiella pneumoniae | 0 (0.00) | 5 (17.86) | 5 (11.11) | 0.174 |
| Influenza A virus | 2 (11.76) | 2 (7.14) | 4 (8.89) | 1.000 |
| Haemophilus influenzae | 0 (0.00) | 4 (14.29) | 4 (8.89) | 0.275 |
| Streptococcus pneumoniae | 1 (5.88) | 2 (7.14) | 3 (6.67) | 1.000 |
| Pseudomonas aeruginosa | 2 (11.76) | 0 (0.00) | 2 (4.44) | 0.137 |
| Escherichia coli | 0 (0.00) | 1 (3.57) | 1 (2.22) | 1.000 |
| Staphylococcus aureus | 0 (0.00) | 1 (3.57) | 1 (2.22) | 1.000 |
| Proteus mirabilis | 0 (0.00) | 1 (3.57) | 1 (2.22) | 1.000 |
| Coronavirus | 1 (5.88) | 0 (0.00) | 1 (2.22) | 0.378 |
| Radiographic imaging | ||||
| Bronchial wall thickening | 10 (58.82) | 20 (71.43) | 30 (66.67) | 0.384 |
| Ground‐glass opacity | 4 (23.53) | 9 (32.14) | 13 (28.89) | 0.780 |
| Patch exudation | 10 (58.82) | 17 (60.71) | 27 (60.00) | 0.900 |
| Negative | 0 (0.00) | 2 (7.14) | 2 (4.44) | 0.519 |
| Unilateral infiltration | 6 (35.29) | 1 (3.57) | 7 (15.56) | 0.015 |
| Bilateral infiltration | 11 (64.71) | 25 (89.29) | 36 (80.00) | 0.106 |
Note: Data are or n (%). p values were calculated by the Mann–Whitney test, χ 2 test, or Fisher’s exact test, as appropriate.
3.5. Treatment and Outcome
All cases received respiratory therapy support of different durations and methods, including 34 cases (75.56%) with nasal cannula oxygen, 5 cases (11.11%) with high‐flow humidification therapy device, and 6 cases (13.33%) with mechanical ventilation, among which 3 cases (6.67%) were noninvasive and 3 cases (6.67%) were invasive. Antibiotics were used in 44 cases (97.78%), intravenous corticosteroids were used in 17 cases (37.78%), and nebulized therapy was used in 38 cases (84.44%).
Forty‐two cases (93.33%) were discharged, and 3 cases (6.67%) died. Days of hospitalization were 12.39 ± 8.11 days, as shown in Table 5.
TABLE 5.
Treatment and outcome n (%).
| 60–79 years (n = 17) | ≥ 80 years (n = 28) | Total (n = 45) | p value | |
|---|---|---|---|---|
| Treatment | ||||
| Nasal cannula oxygen | 12 (70.59) | 22 (78.57) | 34 (75.56) | 0.805 |
| High‐flow humidification therapy device | 3 (17.65) | 2 (7.14) | 5 (11.11) | 0.550 |
| Noninvasive mechanical ventilation | 2 (11.76) | 1 (3.57) | 3 (6.67) | 0.651 |
| Invasive mechanical ventilation | 0 (0.00) | 3 (10.71) | 3 (6.67) | 0.435 |
| Antibiotics | 17 (100.00) | 27 (96.43) | 44 (97.78) | 1.000 |
| Intravenous corticosteroids | 6 (35.29) | 11 (39.29) | 17 (37.78) | 0.789 |
| Nebulized therapy | 14 (82.35) | 24 (85.71) | 38 (84.44) | 1.000 |
| Outcome | ||||
| Discharged | 16 (94.12) | 26 (92.86) | 42 (93.33) | 1.000 |
| Died | 1 (5.88) | 2 (7.14) | 3 (6.67) | 1.000 |
| Days of hospitalization | 11.36 ± 7.38 | 9.56 ± 5.68 | 12.39 ± 8.11 | |
Note: Data are or n (%). p values were calculated by the Mann–Whitney test, χ 2 test, or Fisher’s exact test, as appropriate.
4. Discussion
Five findings were reported in this study: (1) The antiseasonal epidemic situation of RSV caused by the epidemic and control mode of COVID‐19 has passed, and the seasonality of prevalence has returned to normal; (2) the RSV infection rate among elderly ARI hospitalized patients is higher than previously reported; (3) the proportion of lymphocyte decline and respiratory failure was higher than that previously reported; (4) the proportion of heart failure and respiratory failure in elderly RSV patients increases with age; and (5) the laboratory examination, imaging examination, and treatment scheme of elderly RSV patients have their obvious characteristics, which should be paid special attention to.
RSV belongs to the Pneumoviridae family and the Orthopneumovirus genus and is one of the most important viral pathogens causing acute lower respiratory tract infections in children under 5 years old, the elderly, and immunocompromised people. A 4‐year prospective cohort study showed that RSV infection is observed in 3%–7% of healthy elderly people and 4%–10% of adults with chronic cardiopulmonary diseases every year [4]. The seasonality of RSV in China is characterized by starting in November, peaking from December to February, and ending in April of the following year [5]. During the COVID‐19 epidemic, nonpharmacological interventions (NPI) disrupted the typical seasonality of infections with other common respiratory pathogens, and outbreaks of RSV were reported in many places after relaxation (usually several months later) [1, 2]. In this study, RSV accounted for the second place of the main six respiratory virus detection rates and peaked in January and February, which is consistent with the seasonal transmission characteristics before the COVID‐19 epidemic, and no out‐of‐season epidemics were found. Considering that the NPI has been relaxed for more than a year, the prevalence of RSV may be close to normal.
The infection rate in the peak month (January) is 24.11%, close to the 26.5% reported by He [6]. The 4‐month average infection rate was 12.16%, which was higher than the corresponding data in Germany (2.9%∼9.1%) [7] and the United Kingdom (9.6%) [8]. This may be due to the fact that PCR laboratories have become more popular in recent years, and more medical institutions are using PCR to replace the previous rapid antigen test technology and improve the infection rate of RSV. RSV infection in adults has been reported to increase with age [9], but this study compared the infection rate of RSV in two age groups, and there was no statistical difference, which may be related to the short duration of the study and the small sample size.
We observed that cough (97.78%), sputum production (95.56%), and dyspnea (68.89%) were the main manifestations of RSV infection in the elderly in the early stages of the disease. The fever rate (57.78%) is low, and the proportion of upper respiratory tract symptoms such as sore throat, rhinorrhea, and nasal congestion is less than 20%, which was consistent with the rapid progression of the disease and the symptoms of wheezing, shortness of breath, and dyspnea reported in the literature [3, 10]. More than half of the elderly RSV‐infected patients in this study finally developed dyspnea during the clinical course, which is consistent with Luo’s report (68.89% vs. 52.6%) [11]. The reason is that the respiratory system is easily involved after viral infection, causing airway obstruction accompanied by infiltration around the bronchi and mucous membrane edema, bronchial smooth muscle spasm, and subsequent high airway reactivity; secondly, a number of studies have found that among elderly RSV‐infected people, comorbidities are more common [12]. All cases in this study had one or more comorbidities (cardiovascular and cerebrovascular diseases, chronic respiratory diseases, diabetes, etc.), and RSV was the main cause of the exacerbation of airway diseases such as asthma and COPD.
Patients with comorbidities like cardiovascular disease and chronic lung disease are more likely to develop symptoms of RSV disease [13]. For elderly patients, the infection rate of RSV in patients with COPD, asthma, diabetes, and heart failure is much higher than those who have no such conditions, which is 3.51∼13.41 times, 2.27∼2.52 times, 2.35∼6.44 times, 3.75∼6.46 times, and 3.99∼7.63 times, respectively [14]. After RSV infection, it will aggravate the original respiratory and cardiovascular diseases, induce respiratory failure, heart failure, and others.
In this study, 37.78% of patients had elevated NT‐proBNP, and 33.33% of patients had elevated hs‐cTni; this may be related to myocardial injury and cardiac insufficiency caused by cardiovascular system involvement after RSV infection. We also performed blood routines, inflammatory indicator tests, liver function tests, blood gas analysis, and other laboratory tests on all patients. The results were: (1) 29 cases (64.44%) had lymphopenia, which was significantly higher than the blood analysis results of RSV‐infected children of all ages reported by Luo et al. [11] and RSV‐infected people of all ages reported by Gong et al. [15], and (2) 27 cases (60.00%) had respiratory failure; this is higher than the infection rate of respiratory failure in elderly RSV patients in Beijing (15.8%) [11] and close to the data reported in Hong Kong (52.8%) [16]. The elderly are immunocompromised, and the condition is more severe after infection, especially for the high‐risk groups with cardiopulmonary and vascular diseases. In addition, RSV infection is usually associated with worsening of heart failure and respiratory failure. Therefore, in the high infection season, RSV should be regarded as a key surveillance project for elderly high‐risk groups.
In this study, 17 cases (47.78%) had mixed pathogen infections at the time of admission, including 14 cases (31.11%) of bacterial infections and 5 cases (11.11%) of viral infections. The proportion of bacterial infections is significantly higher than that of viral infections, and replication in highly differentiated apical ciliated cells in the human airway after RSV infection is considered to be associated [17], resulting primarily in superficial damage to the inner layer of the airways, which predisposes patients to secondary bacterial infections [18]. The low proportion of RSV merging with other viruses may be consistent with the so‐called viral interference phenomenon, in which one virus prevents the growth of the other virus in the case of co‐infection with multiple viruses [19, 20].
Imaging findings of pneumonia are quite variable and usually mildly abnormal, including unilateral or bilateral patchy subsegmental alveolar infiltrates and rarely lobar consolidation. Diffuse interstitial infiltrates, often considered the classic pattern of viral pneumonia, are uncommon (< 1%) [21]. In this study, 2 patients had negative lung imaging, and after CT examination of RSV infection, it showed an airway‐centered disease pattern, accompanied by bronchial wall thickening, ground‐glass opacity, and small focal consolidation. Bilateral lesions were common, and the imaging manifestations were nonspecific.
The treatment of infection was mainly based on supporting symptomatic treatment. All cases received respiratory therapy support for different durations and methods, and the proportion of mechanical ventilation was basically the same as the literature reported (12.5%) [11]. The high antibiotic prescribing rate (97.78%) likely reflects diagnostic uncertainty and concern for bacterial superinfection, particularly in patients with COPD and imaging abnormalities. However, only 31.11% had confirmed bacterial co‐infection, suggesting potential overuse. This highlights the importance of considering more precise diagnostic tools, such as procalcitonin‐guided protocols, to reduce unnecessary antibiotic exposure and enhance antimicrobial stewardship in similar cohorts. Antibiotics were used in 41 cases (91.11%) and intravenous corticosteroids in 17 cases (37.78%), which was higher than reported, especially antibiotic use (91.11% vs. 77%) [22]. The reason is the lack of specificity in the imaging of patients with RSV infection, and the elderly patients with RSV infection often have comorbidities, especially respiratory diseases. Doctors always treat patients empirically with antibiotics after admission, which increases the rate of antibiotic use. Indications for antibiotic use need to be further standardized. In addition, data on vaccination status (influenza, pneumococcal, COVID‐19) and frailty‐related outcomes (e.g., activities of daily living, Barthel Index, presence of dementia) were not collected, which may represent important unmeasured confounders, particularly in the ≥ 80‐year‐old group.
Author Contributions
Xuedan Li is responsible for the definition of intellectual content, literature research, data analysis, statistical analysis, manuscript preparation and editing; Qing Miao is responsible for the guarantor of integrity of the entire study, study concepts and design, manuscript review; Bingtao Yu is responsible for the data analysis; Yanbo Han is responsible for the clinical studies, experimental studies; and Chaofan Feng and Suqin Lu are responsible for the data acquisition.
Funding
The authors received no specific funding for this work.
Disclosure
All authors read and approved the final manuscript.
Ethics Statement
This study was conducted in accordance with the Declaration of Helsinki and was approved by the Medical Ethics Committee of Beijing Fengtai YouAnMen Hospital (20240506), and patient consent statements have been granted an exemption. Written informed consent was obtained from all participants prior to their inclusion in the study. All procedures involving human subjects were performed in compliance with institutional and national ethical standards. No animal experiments were conducted in this study.
Consent
Please see the Ethics Statement.
Conflicts of Interest
The authors declare no conflicts of interest.
Acknowledgments
The authors have nothing to report.
Li, Xuedan , Miao, Qing , Yu, Bingtao , Han, Yanbo , Feng, Chaofan , Lu, Suqin , A Study on Clinical Features of Respiratory Syncytial Virus in Acute Respiratory Tract Infection in Elderly Hospitalized Patients in Winter, Canadian Respiratory Journal, 2026, 6631479, 8 pages, 2026. 10.1155/carj/6631479
Academic Editor: Bushra Akhtar
Contributor Information
Qing Miao, Email: miaoqing553@163.com.
Bushra Akhtar, Email: lbuch@wiley.com.
Data Availability Statement
All data generated or analyzed during this study are included in this published article. Further inquiries can be directed to the corresponding author.
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Data Availability Statement
All data generated or analyzed during this study are included in this published article. Further inquiries can be directed to the corresponding author.